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R. Ll.Brown J. R. Hollwey A. J. Van Der Weele E. H. Thompson 《The Photogrammetric Record》1971,7(38):182-200
Four papers were read during the first symposium to be held by the Photogrammetric Society, at the University of Birmingham on 3rd and 4th April. Major General R. LI. Brown examined the staff structure of the organisations engaged upon the photogrammetric production of maps in the United Kingdom. Mr. J. R. Hollwey outlined the syllabus for a new Higher National Certificate in photogrammetry during a session which was devoted to education and qualifications. Subsequently, Professor A. J. van der Weele explained the evolution of the courses at ITC. By way of contrast, Professor E. H. Thompson attempted a forecast of developments in photogrammetry during the next decade. The papers succeeded in initiating prolonged discussion among the 80 members who attended. 相似文献
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E. H. Thompson 《The Photogrammetric Record》1971,7(38):157-181
The paper describes a new type of photogrammetric plotter based on first order formulae. It differs from other attempts at this, in that all the implications of these formulae are accepted with the three principal consequences that the operator views a model that is free of y-parallax, that all effects of convergence of the pictures, including errors in the vertical scale, are removed and that geometrical errors in the heights do not increase with increasing ground elevations. The principles lead to a robust, cheap plotter. 相似文献
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E. H. Thompson 《The Photogrammetric Record》1964,4(23):337-366
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We report optically stimulated luminescence (OSL) dating results from the Old Cedar midden in St. Joseph Peninsula State Park, located between the Gulf of Mexico and St. Joseph Bay near Port St. Joe, FL, USA. The Old Cedar site (8GU85) is located on top of a relict beach ridge which is actively eroding into St. Joseph Bay. Old Cedar is noted for its conch shell tool assemblage, otherwise rare at northwest Florida archaeological sites, and is believed to have been utilized during the Late Woodland Weeden Island and possibly the Fort Walton periods [Benchley, E.D., Bense, J.A., 2001. Archaeology and history of St. Joseph Peninsula State Park: Phase I investigations. Report of Investigations, No. 89, University of West Florida Archaeology Institute]. After removing surficial erosion deposits, we extracted OSL core samples from both the midden layer and the underlying beach ridge. The resulting OSL age is compared with the age of another beach ridge on St. Joseph Peninsula. We hope that this study will aid in the investigation and conservation of Old Cedar specifically and other Weeden Island sites in the St. Joseph Bay area. 相似文献
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A detailed understanding of channel forming and maintenance processes in mountain streams requires some measurement and/or prediction of bed load transport and sediment mobility. Traditional field based measurements of such processes are problematic because of the high formative discharges characteristic of such streams. The application of Optically Stimulated Luminescence (OSL) dating is proposed here as a new way of determining actual residency times of fine sediments and consequently validating selected predictions for the entrainment of sediment in these streams. Model predictions of sediment mobility for selected step-pool and plane-bed channels in a mountain catchment in south eastern Australia are initially calculated using equations of hydraulic competence and the one-dimensional HEC-RAS model. Results indicate that floods exceeding bankfull with recurrence intervals up to 13 years are competent to mobilise the maximum overlying surface grain sizes at both sites. OSL minimum age model results from 7 samples of well bleached quartz in the fine matrix particles indicate general agreement with selected competence equations. The apparent long (100–1400 y) burial age of most of the mineral quartz, however, suggests that competent flows are not able to flush all subsurface fine-bed material. The depth of maximum bed load exchange (flushing) was limited to ≤ twice the depth of the overlying D90 grain size. Application of OSL in this study provides important insight into the nature of storage and flushing of matrix material in mountain streams. 相似文献
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Alexander Thompson 《Climatic change》2006,78(1):7-29
This article analyzes climate change from the perspective of international politics. In the anarchy of the international system, various cooperation problems have stalled the formation of an effective climate regime at the international level. Obstacles occur at three stages of regime formation: the bargaining stage, the transition stage, and the implementation stage. The importance of the transition stage of cooperation, which takes place between the signing of an agreement and its entry into force, has been overlooked by international relations scholars and is particularly important in the climate case. The article assesses the possibility of applying `adaptive management' principles to climate change as a partial response to these political obstacles. While such an approach has significant appeal given the uncertainty surrounding the human-climate interface, its experimental, top-down characteristics are not politically feasible at the international level. I recommend certain modifications of existing institutions and practices to improve international information sharing and facilitate efficient learning. These changes would serve to promote a decentralized and passive – and thus politically viable – version of adaptive management, an effective approach to dealing with climate change at the global level. 相似文献